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Convert image to byte array C# in a proper way

My problem is that I need to convert an image to a byte array to obtain its pixels.
My image size is 268x188 and when I use the property PixelsFormat it returns Format24bppRgb, so I understand that each pixel contains 3 bytes.
If this is true, the size of the pixels should be 268*188*3 = 151152 bytes, but the byte array that I am creating has a size of 4906 bytes, which is the size of the image file in my computer.
I don´t know if there is another way to obtain these pixels or you can only obtain image file size.

If you want to ignore the header and the compression of the file you can do the following.
var path = ...
using(var image = Image.FromFile(path))
using(var bitmap = new Bitmap(image))
{
var bitmapData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, bitmap.PixelFormat);
var bytesPerPixel = 4; // bitmapData.PixelFormat (image.PixelFormat and bitmapData.PixelFormat can be different)
var ptr = bitmapData.Scan0;
var imageSize = bitmapData.Width * bitmapData.Height * bytesPerPixel;
var data = new byte[imageSize];
for (int x = 0; x < imageSize; x += bytesPerPixel)
{
for(var y = 0; y < bytesPerPixel; y++)
{
data[x + y] = Marshal.ReadByte(ptr);
ptr += 1;
}
}
bitmap.UnlockBits(bitmapData);
}

To get image pixel try this:
public static byte[] GetImageRaw(Bitmap image)
{
if (image == null)
{
throw new ArgumentNullException(nameof(image));
}
if (image.PixelFormat != PixelFormat.Format24bppRgb)
{
throw new NotSupportedException("Invalid pixel format.");
}
const int PixelSize = 3;
var data = image.LockBits(
new Rectangle(Point.Empty, image.Size),
ImageLockMode.ReadWrite,
image.PixelFormat);
try
{
var bytes = new byte[data.Width * data.Height * PixelSize];
for (var y = 0; y < data.Height; ++y)
{
var source = (IntPtr)((long)data.Scan0 + y * data.Stride);
// copy row without padding
Marshal.Copy(source, bytes, y * data.Width * PixelSize, data.Width * PixelSize);
}
return bytes;
}
finally
{
image.UnlockBits(data);
}
}
Take a look at Bitmap.LockBits

I use this code in ASP.NET application. Very simple:
var imagePath = GetFilePathToYourImage();
using (var img = System.IO.File.OpenRead(imagePath))
{
var imageBytes = new byte[img.Length];
img.Read(imageBytes, 0, (int)img.Length);
}

Wrong generated TIf image using WriteableBitmap::WritePixels in c#

I changed pixel RGB value for a TIF image, but the generated tif image is not correct.
I use C# since there are some APIS for encoding and decoding TIF image format. My code is shown below.
public partial class Form1 : Form
{
private static int bytesPerPixel = 4;
private int width;
private int height;
byte[] bytes;
BitmapSource bitmapSource;
FormatConvertedBitmap convertedBitmap;
public Form1()
{
InitializeComponent();
}
private void openToolStripMenuItem_Click(object sender, EventArgs e)
{ .....
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
// Open the selected file to read.
string fileName = openFileDialog1.FileName;
pictureBox1.Load(fileName);
// Open a Stream and decode a TIFF image
Stream imageStreamSource = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);
TiffBitmapDecoder decoder = new TiffBitmapDecoder(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
bitmapSource = decoder.Frames[0];
convertedBitmap = new FormatConvertedBitmap(bitmapSource, PixelFormats.Bgra32, null, 0);
bytesPerPixel = (convertedBitmap.Format.BitsPerPixel + 7) / 8;
width = convertedBitmap.PixelWidth;
height = convertedBitmap.PixelHeight;
bytes = new byte[width * height * bytesPerPixel];
convertedBitmap.CopyPixels(bytes, (convertedBitmap.PixelWidth * convertedBitmap.Format.BitsPerPixel + 7) / 8, 0);
for (int i = 0; i < width; i++) {
for (int j = 0; j < height; j++) {
Color color = GetPixel(bytes, i,j, bytesPerPixel);
if (i < width / 2 || j < height / 2)
setPixel(bytes, i, j, bytesPerPixel, (byte)(0), (byte)(0), (byte)(0));
else {
setPixel(bytes, i, j, bytesPerPixel, (byte)(255), (byte)(255), (byte)(255));
}
}
}
}
}
private static Color GetPixel(byte[] bgraBytes, int x, int y, int width)
{
var index = (y * (width * bytesPerPixel) + (x * bytesPerPixel));
return Color.FromArgb(
bgraBytes[index + 3],
bgraBytes[index + 2],
bgraBytes[index + 1],
bgraBytes[index]);
}
private static void setPixel(byte[] bytes, int x, int y, int width, byte r, byte g, byte b) {
var index = (y * (width * bytesPerPixel) + (x * bytesPerPixel));
bytes[index] = r; bytes[index + 1] = g; bytes[index + 2] = b;
}
private void saveToolStripMenuItem_Click(object sender, EventArgs e)
{ ................
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
int stride = width *8;
// Define the image palette
BitmapPalette myPalette = BitmapPalettes.WebPalette;
// Creates a new empty image with the pre-defined palette
var image = new WriteableBitmap(convertedBitmap);
image.WritePixels(new Int32Rect(0, 0, convertedBitmap.PixelWidth, convertedBitmap.PixelHeight), bytes,
(convertedBitmap.PixelWidth * convertedBitmap.Format.BitsPerPixel + 7) / 8, 0);
FileStream stream = new FileStream(saveFileDialog1.FileName, FileMode.Create);
TiffBitmapEncoder encoder = new TiffBitmapEncoder();
TextBlock myTextBlock = new TextBlock();
myTextBlock.Text = "Codec Author is: " + encoder.CodecInfo.Author.ToString();
encoder.Compression = TiffCompressOption.Zip;
encoder.Frames.Add(BitmapFrame.Create(image));
encoder.Save(stream);
stream.Dispose();
}
}
}
In the code, a tif image is read and its pixel RGB is copied to the byte[] bytes which is a class field member. After modifying all pixel RGB color (by 255 -), the bytes is then used to initilize another image and writen to the disk.
There is no error during runtime, but the generated tif image is not the same as i expected. The generated image is the same as original one, which is not correct.
Could anyone explain the reason that the generated image the same as input one? It seems the writePixel() does not take effect. During debug, i do find the bytes parameter in writePixel has been updated. I do not know the reason, as i am not very skill at C#, nor Image format. The original code are from
https://msdn.microsoft.com/en-us/library/aa969817%28v=vs.110%29.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-1
and
TIFF file parsing in C#

PNG extracted via from PDF via Flate decoding is unrecognisable - C#

The C# software I'm involved with writing has a component that involves the reading of barcodes from scanned documents. The PDFs themselves are opened using PDFSharp.
Unfortunately we're encountering an issue with the process when it involves Flate Decoding of PDFs. Basically, all we get is a bunch of fuzz, which means there is no barcode to check and the document is not recognised.
Our code (which we shamelessly "borrowed" from another Stack Overflow case!) is as follows:
private FileInfo ExportAsPngImage(PdfDictionary image, string sourceFileName, ref int count)
{
//This code basically comes from http://forum.pdfsharp.net/viewtopic.php?f=2&t=2338#p6755
//and http://stackoverflow.com/questions/10024908/how-to-extract-flatedecoded-images-from-pdf-with-pdfsharp
string tempFile = string.Format("{0}_Image{1}.png", sourceFileName, count);
int width = image.Elements.GetInteger(PdfImage.Keys.Width);
int height = image.Elements.GetInteger(PdfImage.Keys.Height);
int bitsPerComponent = image.Elements.GetInteger(PdfImage.Keys.BitsPerComponent);
var pixelFormat = new PixelFormat();
switch (bitsPerComponent)
{
case 1:
pixelFormat = System.Drawing.Imaging.PixelFormat.Format1bppIndexed;
break;
case 8:
pixelFormat = System.Drawing.Imaging.PixelFormat.Format8bppIndexed;
break;
case 24:
pixelFormat = System.Drawing.Imaging.PixelFormat.Format24bppRgb;
break;
default:
throw new Exception("Unknown pixel format " + bitsPerComponent);
}
var fd = new FlateDecode();
byte[] decodedBytes = fd.Decode(image.Stream.Value);
byte[] resultBytes = null;
int newWidth = width;
int alignment = 4;
if (newWidth % alignment != 0)
//Image data in BMP files always starts at a DWORD boundary, in PDF it starts at a BYTE boundary.
//Most images have a width that is a multiple of 4, so there is no problem with them.
//You must copy the image data line by line and start each line at the DWORD boundary.
{
while (newWidth % alignment != 0)
{
newWidth++;
}
var copy_dword_boundary = new byte[height, newWidth];
for (int y = 0; y < height; y++)
{
for (int x = 0; x < newWidth; x++)
{
if (x <= width && (x + (y * width) < decodedBytes.Length))
// while not at end of line, take orignal array
copy_dword_boundary[y, x] = decodedBytes[x + (y * width)];
else //fill new array with ending 0
copy_dword_boundary[y, x] = 0;
}
}
resultBytes = new byte[newWidth * height];
int counter = 0;
for (int x = 0; x < copy_dword_boundary.GetLength(0); x++)
{
for (int y = 0; y < copy_dword_boundary.GetLength(1); y++)
{ //put 2dim array back in 1dim array
resultBytes[counter] = copy_dword_boundary[x, y];
counter++;
}
}
}
else
{
resultBytes = new byte[decodedBytes.Length];
decodedBytes.CopyTo(resultBytes, 0);
}
//Create a new bitmap and shove the bytes into it
var bitmap = new Bitmap(newWidth, height, pixelFormat);
BitmapData bitmapData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.WriteOnly, bitmap.PixelFormat);
int length = (int)Math.Ceiling(width * bitsPerComponent / 8.0);
for (int i = 0; i < height; i++)
{
int offset = i * length;
int scanOffset = i * bitmapData.Stride;
Marshal.Copy(resultBytes, offset, new IntPtr(bitmapData.Scan0.ToInt32() + scanOffset), length);
}
bitmap.UnlockBits(bitmapData);
//Now save the bitmap to memory
using (var fs = new FileStream(String.Format(tempFile, count++), FileMode.Create, FileAccess.Write))
{
bitmap.Save(fs, ImageFormat.Png);
}
return new FileInfo(tempFile);
}
Unfortunately, all we get out of it is this http://i.stack.imgur.com/FwatQ.png
Any ideas on where we're going wrong, or suggestions for things we might try would be greatly appreciated.
Cheers

Thanks for the suggestions guys. One of the other developers managed to crack it - it was (as Jongware suggested) a JPEG, but it was actually zipped as well! Once unzipped it could be processed and recognised as normal.

How to create a Byte array that contains a real Image?

Please see my code below.
I want to create a Byte array with data that I can convert into a real image. When I try to run this code I get an argumentException. What do I need to do in the For loop in order to create a legitimate Byte array that will hold data of an image? I don't want to use a real image and convert it to byte array, I want to create an image form random numbers.
Random Rnd = new Random();
public MainWindow()
{
InitializeComponent();
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
Byte[] ByteArray = new Byte[1000];
for (int i = 0; i < 1000; i++)
{
ByteArray[i] = Convert.ToByte(Rnd.Next(9));
}
ImageConverter Convertor = new ImageConverter();
BitmapImage image = (BitmapImage)Convertor.ConvertFrom(ByteArray);
MyImage.Source = image;
}
Notice please that I don't want to work with WinForms types or libraries like system.drawing / bitmap - I only want to use WPF technology.

This is the solution you are looking for, using only WPF technology.
Note that the constant value of 16 used in the stride parameter calculation comes directly from the fact that I am using a 16-bit pixel format.
private void Button_Click_1(object sender, RoutedEventArgs e)
{
Random rnd = new Random();
Byte[] ByteArray = new Byte[(int)MyImage.Width * (int)MyImage.Height * 3];
rnd.NextBytes(ByteArray);
var image = BitmapSource.Create((int) MyImage.Width, (int) MyImage.Height, 72, 72,
PixelFormats.Bgr565, null, ByteArray, (4*((int)MyImage.Width * 16 + 31)/32));
MyImage.Source = image;
}

This just might do the trick for you:
private static Bitmap GenBitmap(int width, int height) {
int ch = 3; //number of channels (ie. assuming 24 bit RGB in this case)
Random rnd = new Random();
int imageByteSize = width * height * ch;
byte[] imageData = new byte[imageByteSize]; //your image data buffer
rnd.NextBytes(imageData); //Fill with random bytes;
Bitmap bitmap = new Bitmap(width, height, PixelFormat.Format24bppRgb);
BitmapData bmData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadWrite, bitmap.PixelFormat);
IntPtr pNative = bmData.Scan0;
Marshal.Copy(imageData, 0, pNative, imageByteSize);
bitmap.UnlockBits(bmData);
return bitmap;
}

I'm not sure how Converter.ConvertFrom works but I prefer to do my bitmaps the lower-level way with Bitmap.LockBits() and a little Marshal.Copy().
See this method:
using System.Drawing;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
static Bitmap CreateRandomBitmap(Size size)
{
// Create a new bitmap for the size requested.
var bitmap = new Bitmap(size.Width, size.Height, PixelFormat.Format32bppArgb);
// Lock the entire bitmap for write-only acccess.
var rect = new Rectangle(0, 0, size.Width, size.Height);
var bitmapData = bitmap.LockBits(rect, ImageLockMode.WriteOnly, bitmap.PixelFormat);
// Calculate the number of bytes required and allocate them.
var numberOfBytes = bitmapData.Stride * size.Height;
var bitmapBytes = new byte[numberOfBytes];
// Fill the bitmap bytes with random data.
var random = new Random();
for (int x = 0; x < size.Width; x++)
{
for (int y = 0; y < size.Height; y++)
{
// Get the index of the byte for this pixel (x/y).
var i = ((y * size.Width) + x) * 4; // 32bpp
// Generate the next random pixel color value.
var value = (byte)random.Next(9);
bitmapBytes[i] = value; // BLUE
bitmapBytes[i + 1] = value; // GREEN
bitmapBytes[i + 2] = value; // RED
bitmapBytes[i + 3] = 0xFF; // ALPHA
}
}
// Copy the randomized bits to the bitmap pointer.
var ptr = bitmapData.Scan0;
Marshal.Copy(bitmapBytes, 0, ptr, numberOfBytes);
// Unlock the bitmap, we're all done.
bitmap.UnlockBits(bitmapData);
return bitmap;
}
Then you can do something like this:
public void Run()
{
using(var bitmap = CreateRandomBitmap(new Size(64, 64)))
{
bitmap.Save("random.png", ImageFormat.Png);
}
}

You can't use random bytes to create an image, because each type of image (bmp, jpeg, png) is constructed with a certain format. The code wouldn't know how to interpret random bytes.
http://en.wikipedia.org/wiki/Image_file_formats

How to change 12-bits and 10-bits raw file to bitmap image using c#

I have 10-bits and 12-bits rawbayer (.raw) file. And i want to convert it to Bitmap image but i am unable to change it. 8-bits or 16-bits raw file changed easily but 10-bits or 12-bits can't be changed.
here is the code for 8-bits raw file to Bitmap.
private void DisplayImage08(string fileName) //Raw file name
{
// Open a binary reader to read in the pixel data.
// We cannot use the usual image loading mechanisms since this is raw
// image data.
try
{
BinaryReader br = new BinaryReader(File.Open(fileName, FileMode.Open));
byte pixByte;
int i;
int iTotalSize = (int)br.BaseStream.Length;
// Get the dimensions of the image from the user
ID = new ImageDimensions(iTotalSize);
width = Convert.ToInt32(ID.txtwidth);
height = Convert.ToInt32(ID.txtheight);
//panel1.Width = width;
//panel1.Height = height;
pictureBox1.Width = width;
pictureBox1.Height = height;
pix08 = new byte[iTotalSize];
//pix08 = new byte[iTotalSize];
for (i = 0; i < iTotalSize; ++i)
{
pixByte = (byte)(br.ReadByte());
pix08[i] = pixByte;
}
br.Close();
int bitsPerPixel = 8;
stride = (width * bitsPerPixel + 7) / 8;
// Single step creation of the image
bmps = BitmapSource.Create(width, height, 96, 96, PixelFormats.Gray8, null,
pix08, stride);
//Bitmap bmp = new Bitmap();
// img.Source = bmps;
Bitmap bt = BitmapFromSource(bmps); //Change Bitmap source to Bitmap
pictureBox1.Image = bt; //Display on pictureBox
pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize;
}
catch (Exception e)
{
}
}
But i want to change 12-bits or 10 bits raw file to Bitmap.
So please help me on this, that how can i change it?
Thanks

This isn't a complete answer by no means, but this code will convert a 12 or 10 bit image, depending on how the data is packed, to a 8 bit image.
// Input data read from file
var pixels = ...
// Output
var bytes = new byte[width * height];
// Sort data
for (var i = 0; i < bytes.Length; i++)
{
if (i % 2 == 0)
{
var index = i * 3 / 2;
bytes[i] = pixels[index];
}
else
{
var index = (i * 3 + 1) / 2;
bytes[i] = pixels[index];
}
}